PENANG, MALAYSIA — Dr. Ali Imron, M.S.I., Head of the Master’s Program in Ilmu Al-Qur’an dan Tafsir(Quranic Studies) at the Faculty of Ushuluddin and Islamic Thought, UIN Sunan Kalijaga Yogyakarta, presented his research findings at the 2nd International Symposium on Hadith 2026, held on Tuesday, October 20, 2026, at the Shangri-La Golden Sands, Penang, Malaysia. The symposium was themed “The Dynamics of Hadith: Classical and Contemporary Approaches, Challenges, and Responses.”

At this international academic forum, Dr. Ali Imron presented a paper titled “The 2016 Turkey Agreement on the Hijri Calendar and the Implementation of Hisab-Rukyat (Astronomical Calculation and Sighting) Hadiths in Indonesia and Malaysia (2016–2026): A Comparative Study.” The study examines the evolution of the 2016 Turkey Agreement on the Hijri calendar and its influence on the application of hadiths concerning hisab (astronomical calculation) and rukyat (sighting of the new moon) in Indonesia and Malaysia over the past decade.

The research stems from the variations in how Quranic verses and hadiths regarding the determination of the beginning of the Hijri month are applied. Although both nations utilize a normative framework centered on rukyat al-hilal (sighting the new crescent moon), the actual practices for determining the start of the month reveal distinct dynamics—particularly concerning the interplay between astronomical calculation (hisab), physical sighting (rukyat), religious authority, and state policy.

Employing a qualitative approach based on literature review and comparative analysis, the study examines documents from the International Congress on the Unification of the Hijri Calendar (held in Istanbul, May 28–30, 2016), decisions issued by the Indonesian Ministry of Religious Affairs, fatwas and resolutions from religious organizations, as well as documents from the Department of Islamic Development Malaysia (JAKIM) and agreements reached under the MABIMS framework. One significant finding presented is that the 2016 Turkey Agreement served as a catalyst for the development of Hijri calendar criteria in Indonesia and Malaysia, even though neither country formally adopted these criteria at an institutional level. The agreement proposed a minimum lunar crescent (hilal) altitude of 5 degrees and an elongation of 8 degrees, based on the principle of a unified date—a single day for the entire Islamic world.

In Indonesia, this development contributed to a shift toward the "Neo-MABIMS" criteria—requiring a lunar crescent altitude of 3 degrees and an elongation of 6.4 degrees—which the government began implementing in Ramadan 1443 AH (April 2022). Meanwhile, Muhammadiyah has officially adopted the Unified Global Hijri Calendar (KHGT), effective from 1446 AH (2024 AD). These differing approaches highlight a plurality of systems for determining the Hijri calendar within Indonesia.

In Malaysia, the Neo-MABIMS criteria remain in use, managed through a centralized determination system overseen by JAKIM. This reflects fundamental differences in the structure of religious authority and policy approaches between the two nations.

Through his comparative analysis, Ali Imron explains that the variations in how hadith—concerning hisab (astronomical calculation) and rukyat (sighting of the lunar crescent)—are applied are not merely a matter of technical astronomy. Rather, these differences are shaped by the structure of religious authority, diverse interpretations of hadith, and the specific policy approaches that have evolved within the national context of each country.

In Indonesia, religious authority and perspectives are distributed among various Islamic civil society organizations, creating space for a diversity of approaches. In contrast, Malaysia employs a more centralized approach, where official decisions serve as the definitive standard for establishing the Hijri calendar.

This study underscores the importance of understanding hadith in relation to scientific advancement, the structure of religious authority, and the broader socio-political context. Thus, the study of hadith is not merely oriented toward textual understanding; it also sheds light on how hadith is applied within the lives of contemporary Muslim communities.

Dr. Ali Imron’s participation in this international symposium represents a contribution by academics from UIN Sunan Kalijaga Yogyakarta toward the advancement of hadith studies through cross-border scholarly dialogue. This comparative research between Indonesia and Malaysia also opens up further discussion regarding the potential for harmonizing the Hijri calendar, as well as the challenges involved in applying hadith-based principles concerning hisab (astronomical calculation) and rukyat (sighting of the new moon) within the Islamic world.

Through international academic forums such as this, it is hoped that the study of hadith will continue to evolve in a manner that is critical, contextual, and interdisciplinary—while simultaneously strengthening the contribution of Indonesian Islamic higher education institutions to the global academic discourse.